This invention relates to an air conditioning system for automotive vehicles, and more particularly to an air condition system of this kind which is capable of adjusting the ratio between air amounts blown through left and right air outlets.
An air conditioning system of this kind is known e.g. from Japanese Utility Model Publication (Kokoku) No. 52-19300, which comprises a pair of left and right air outlets arranged, respectively, at left and right sides of a front wall of a compartment of an automotive vehicle, and a pair of temperature sensors arranged at the left and right sides of the front wall, and a door arranged at a juncture or diverging point from which two passages extend to the respective left and right air outlets, for adjusting the ratio between the flow rates of air blown through the respective air outlets. The door is controlled in response to output from the temperature sensors indicative of temperature values detected at the left and right sides to adjust the ratio between the flow rates of air blown through the left and right air outlets.
On the other hand, in conventional air conditioning systems for automotive vehicles having a central air outlet and left and right air outlets in general, the central air outlet is located at the center of a vent duct and the left and right air outlets are located, respectively, at left and right ends of the vent duct.
However, if the aforementioned arrangement known from Japanese Utility Model Publication (Kokoku) No. 52-19300 is applied to such conventional air conditioning systems for automotive vehicles, the door for adjusting the air flow rate ratio will be arranged at a central portion of the vent duct from which branch the passages leading to the left and right air outlets. As a result, as the door is pivotally moved, not only the ratio between the air flow rates through the left and right air outlets is adjusted, but also the ratio between the air flow rate through a left portion of the central air outlet and that through a right portion thereof is changed. This provides the following disadvantages:
(1) The temperature difference between the left and right sides of the compartment tends to be large, making it difficult to finely control the temperatures at the left and right sides of the compartment; and
(2) When the driver feels hot sunbeam at his right-side body portion (in the case of a vehicle with a steering wheel at the right side), if he controls the door so that the flow rate of air (cold air) blown through the right air outlet, also the flow rate of cold air blown through a right portion of the central air outlet is increased correspondingly, so that an excessive amount of cold air is blown against the right half of the driver's body, which is not good to his health.